The present invention relates to a storage system and a data migration method. This invention is suitable for, for example, a storage system using a tiered storage apparatus as a storage apparatus.
Lately, large-capacity storage apparatuses equipped with low-cost storage devices such as SATA (Serial AT Attachment) disks have been introduced onto the market, and storage resource characteristics, such as cost and quality, have been diversified. With the emergence of these low-price storage apparatuses, not only conventional storage solutions for online data, but in addition new ones directed at compliance related markets, for example data archival, etc., have been coming on to the market. So, there has been an urgent need to integrate multiple SAN (Storage Area Network) environments and utilize various different storage resources efficiently and effectively.
Meanwhile, data lifecycle management (DLCM) has been receiving attention lately, and in light of reducing storage management costs, high emphasis is being placed on relocating data to the most suitable storage resource according to data priorities that change over time, and supporting data migration in each DLCM phase between volumes in a storage apparatus.
As a conventional method for allocating the most suitable volume in data migration, for example, JP-A-2004-334561 has introduced a method for managing each volume's actual performance (such as response speed to data input/output requests) and the volume performance required by each application, and in data migration, allocating the data migration target volume that is most suitable for each application. Also, JP-A-2002-305415 has introduced a method for acquiring statistical operational information on volumes used by an application and providing that information to a user, and by utilizing this technique, a user can select a data migration target volume based on that statistical operational information.